Muslims are allowed to eat food prepared by any human as long as the food is clean, healthy, and prepared with halal (lawful) ingredients. It is not required in the Shari`ah to have Muslim cooks and food servers.
Sheikh Ahmad Kutty, a senior lecturer and Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada stated the following: Muslims are allowed to eat lawful foods prepared by anyone, whether they are Muslims or non-Muslims, this includes Hindus, Sikhs, Christians, Jews, et cetera. This is a matter of common knowledge in Islam.
The foods that are considered as essentially unlawful for Muslims to consume have been stated in the following verse: [He has forbidden to you only carrion, and blood, and the flesh of swine, and that over which any name other than God’s has been invoked; but if one is driven by necessity — neither coveting it nor exceeding his immediate need — no sin shall be upon him: for, behold, God is much-forgiving, a dispenser of grace.] (Al-Baqarah 2:173)
To the above is added intoxicants of all sorts as mentioned in the Qur’an (5: 90-91), any of the above items prepared by a non-Muslim or Muslim is unlawful for Muslims to consume.
Food such as vegetables, seafood, and meat (if slaughtered in a halal way) is lawful to consumed without any inhibition, regardless of whether the chef is a Muslim or non-Muslim and regardless of whether it is served by Muslims or non-Muslims.
The Prophet (peace and blessings be upon him), as well as his companions, used to drink water and eat foods prepared by their relatives and fellow countrymen who were mostly pagans in the early times. They only abstained from foods that were considered as unlawful such as carrion, foods immolated to idols, intoxicants, et cetera.
When the companions of the Prophet (peace and blessings be upon him) ventured out of Arabia, they never refrained from eating foods prepared by the locals. They only stayed away from those foods which had been declared as haram.
In conclusion, Muslims are allowed to eat all foods that are considered lawful for us, whether they are prepared or served by Muslims or non-Muslims.